text: The demonstration starts with boiling water inside the can. As the water is boiled, water vapor is created and fills the space inside the can which then pushes the air out.
  HO → HO
  Then, inverting a water vapor-filled can into a water bath causes the water vapor to rapidly condense back to liquid water. The condensation of water reduces pressure inside the can, so the higher pressure outside the can makes the can collapse.
  HO → HO